So im putting back together my engine, and ive come across a threaded hole that i KNOW had some sort of sensor in it (off of memory, and a sensor cable leads right down to it). If looking at the engine, it is on the bottom - just to the right of the timing cover - just to the left of the oil filter - and threaded into the the block. the sensor hookup almost looks identical to a coolant temp line. is anyone able to solve my mystery ?